The present invention relates to a sealing arrangement for a machine having a shaft, particularly for a fluid flow pump. Such a sealing arrangement includes an impeller wheel, a counter-ring cooperating with the impeller wheel, a slide ring seal, and a connecting element which holds all the parts together.
German Pat. No. 2,729,928 discloses a centrifugal pump equipped with an integrated sealing unit. An impeller wheel made of steel or fiber reinforced plastic is firmly connected with a hub made of metal, which could be a sintered metal. At the free end of the hub, a counter-ring is disposed through the intermediary of an elastomer body. Starting from the free end of the hub, either a metallic connecting element or a separate connecting element shaped out of the elastomer material of the counter-ring extends axially to behind the slide ring seal. The drawback of this type of structure is that the relatively compact connection of impeller wheel and hub is relatively heavy and is thus rather expensive to produce. Moreover, the counter-ring, which in many cases is made of a brittle material, as for example ceramic, cannot be integrated with the impeller wheel to thus obtain a shorter structural unit. Further, an additional connecting body, be it of elastomer material or metal, is required, and is absolutely necessary to connect the impeller wheel and the hub, respectively, with the slide ring seal so as to form an installable unit.
German Offenlegungsschrift [Laid-Open Patent Application] No. 2,623,583 discloses a circulating pump, particularly a coolant pump for a motor vehicle, in which a slide ring seal, impeller wheel and counter-ring are combined into an installable unit such that the slide ring seal is provided with a housing which includes the counter-ring, and the counter-ring is fixed to the impeller wheel through the intermediary of an elastomer body. The metal impeller wheel here as well is unable to directly accomodate a counter-ring made of a brittle material without requiring the intermediary of an elastomer layer. Moreover, a separate connecting member is again required to obtain the installable unit.